选择适合你的方法计算,并写出计算过程.

1个回答

  • 解题思路:(1)(4)(5)(7)运用乘法分配律解答,

    (2)运用减法性质解答,

    (3)运用乘法交换律和结合律解答,

    (6)(8)依据四则运算顺序:先算第二级运算,再算第一级运算,如果只含有同一级运算,按照从左到右顺序计算,有括号先算括号里面的顺序解答,

    (1)(125+19)×8,

    =125×8+19×8,

    =1000+152,

    =1152;

    (2)666-(309+266),

    =666-266-309,

    =400-309,

    =91;

    (3)75×2×7×4,

    =(75×4)×(2×7),

    =300×14,

    =4200;

    (4)125×(800-8),

    =125×800-125×8,

    =100000-1000,

    =99000;

    (5)24×24+76×24,

    =(24+76)×24,

    =100×24,

    =2400;

    (6)5000-666÷37×34,

    =5000-18×34,

    =5000-612,

    =4388;

    (7)29×75+72×75-75,

    =(29+72-1)×75,

    =100×75,

    =7500;

    (8)7800÷[300+5×(66+134)],

    =7800÷[300+5×200],

    =78000÷1300,

    =60.

    点评:

    本题考点: 整数四则混合运算;运算定律与简便运算.

    考点点评: 本题主要考查学生依据四则运算顺序,以及正确运用简便方法解决问题的能力.